Xin Shen University of Waikato   Department of Economics University of Waikato Private Bag 3105 Hamilton, Waikato 3240 New Zealand   xs67@waikato.ac.nz             JEL Areas: E2 : Macroeconomics: Consumption, Saving, Production, Employment, and Investment: General (includes Measurement and Data) E6 : Macroeconomic Policy, Macroeconomic Aspects of Public Finance, and General